I tried the keymap editor, but it didn't help much. And, the Logitech Harmony is rather expensive, IMO. I've rethought my situation and decided to look for a Samsung Smart TV without the 4K UHD functionality (since there's no streaming sources that offer 4K content that I use anyways). 720p is the maximum that I've seen. I ordered another TV (due in Monday) that's pretty much a larger version of what I already have. Just something bigger is all I really wanted.
Thanks for the reply, Iridium. :). I do appreciate it.